High Lockout
F006 on Intergas Xtreme 24

Your boiler thinks it sees a flame even when the gas should be turned off, which prevents it from starting up safely.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Flame simulation.

What causes this fault?

This fault occurs when the boiler's sensors detect an electrical current that mimics a flame, even though the burner hasn't actually ignited. The most common reasons are a moisture-damaged ignition lead or a faulty electrode that is sending a false 'flame present' signal back to the main control board.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F000View →F001View →F005View →

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